1. Field of the Invention
The present invention is generally directed towards starch that has been modified with an organic acid anhydride reagent and methods of preparing the same. In certain embodiments, starch produced according to the present invention exhibits good water solubility and emulsifying characteristics when compared with conventional starches. Further, methods of preparing modified starches according to the present invention do not require further treatment with acids, other than the organic acid anhydride reagent, or enzymes to degrade the starch and make it water soluble.
2. Description of the Prior Art
Native starch is partially crystalline and not soluble in water at room temperature. Also, native starch molecules are hydrophilic and do not possess emulsifying properties. A number of references such as U.S. Pat. Nos. 2,661,349 and 6,037,466 disclose introducing hydrophobic groups to the starch by reaction with cyclic dicarboxylic acid anhydrides so that the starch can be used as an emulsion stabilizer.
Octenyl succinc acid anhydride (OSA) treated starch, prepared by adding up to 3% OSA, has been approved by the FDA for food use and can be used in food and beverage applications, such as in encapsulation of vitamins and flavors. Starch may also be reacted with greater than 3% OSA for non-food applications, such as in oil- and petroleum-based cosmetics, or pharmaceutical pastes, alcohol-based lotions, body deodorant sprays, and encapsulation of fragrances, clouds, and oils. Conventionally, OSA-modified starch must undergo acid hydrolysis or enzymatic conversion in order to be converted (or degraded) and rendered water soluble at room temperature. Modified starch that undergoes this further processing may contain acid or enzyme residues.